New Quadratic Self-Assembly of Double-Decker Phthalocyanine on Gold(111) Surface: From Macroscopic to Microscopic Scale

Abstract

Unveiling the self-organization mechanism of semiconducting organic molecules onto metallic surfaces is the rst step to design hybrid devices in which the selfassembling is exploited to tailor magnetic properties. In this study, doubledecker rare-earth phthalocyanines, namely lutetium phthalocyanine (LuPc 2), are deposited on Au(111) gold surface forming large scale self-assemblies. Global and local experimental techniques, namely grazing incidence X-ray diraction and scanning tunneling microscopy, supplemented by density functional theory calculations with van der Waals corrections, give insight of the molecular structural arrangement in the thin lm and the self-organization at the surface. Our results show unambiguously that the two plateaus of the doubledecker phthalocyanine present a dierent rotation than the isolated molecule. This is evidenced by density functional theory simulations of optimized LuPc 2 monolayer showing a perfect agreement with experimental ndings. Moreover, the stabilized structure of double layers reveals an eclipsed conguration of the molecules in the stacking, having the ligand plateaus parallel to the gold surface. The high crystallinity of the molecular assembly and its weak electronic coupling with the metallic substrate is expected to open new perspective in the design of optoelectronic or magnetic devices.

Lanthanide bisphthalocyanine single-molecule magnets: A DFT survey of their geometries and electronic properties from lanthanum to lutetium

“…Given the nanometer-sized dimensions of LnPc 2 (the width of a single unsubstituted Pc ligand is about 1.5 nm) and their rather high molecular weight of >1000 Da, a natural choice of the computational methodology is density functional theory (DFT). Indeed, there is a number of studies, which employed pure and hybrid DFT functionals to study LnPc 2 systems [3,[26][27][28][29][30][31][32][33][34][35], though it does not seem to be particularly large. Here it is appropriate to make the following important observations.…”

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

“…Based on the low-dimensional studies, we expect to find multiple stable adsorbate structures in the 6D search, with varying molecular orientations and both chemical and dispersive bonding. Given the observed energy ranges, we conclude that the optimal search range for the height of the molecule in the 6D search is z ∈ [4,7] Å. The range is sufficiently broad to include all the minima and avoids high-energy peaks in the closest approach of the molecule to the surface.…”

“…Assemblies of organic molecules on surfaces have been studied experimentally, for example with X-ray diffraction [4,5], scan-ning tunneling microscopy [6][7][8] and atomic force microscopy (AFM) [9][10][11]. These methods have a considerable resolution in imaging planar surface structures, but interpreting images of bulky three-dimensional molecules on surfaces can be difficult, which prevents an accurate structure determination.…”

Revealing the Interplay Between Covalent and Non-Covalent Interactions Driving the Adsorption of Monosubstituted Thiourea Derivatives on the Au(111) Surface

“…We consider that the results here presented provide a theoretical strategy to reveal the molecule–surface interactions, which in view of the growing interest in this type of system − can be helpful to achieve a better understanding of the properties in hybrid organic–metal interfaces. The interest of such systems lies in their potential applications such as biosensors or atmospheric sensors.…”